Preamble/warning: So far, I do not do any mathematics on my computer. I’m interested in it and so I know a bit about it, but the only reason I post this as an answer is because it is just too lengthy for a comment. The following are immature estimations, but I really can’t imagine that I’m off by too much with them.
On “Would it be possible advisable …?”: Yes and no.
Yes: Although many of the statements (theorems) you encounter are fairly abstract and may even involve the highly non-constructive axiom of choice, there are proof assistants. (I recently learned about Isabelle which is based on ML and has similarities to Haskell.) It is possible to prove many abstract theorems using such tools. With Sage you can compute a lot of abstract things. So there are a lot of ways to do mathematics in a programming fashion.
(So, proof assistants are, I think, the only way to “implement” textbooks problems that involve proofs – and they are a huge amount of the problems and very essential to understanding.)
No: Implementing proofs and calculations means being very formal. I don’t even know if there are theoretical limits to the class of formal proofs that can be checked by a computer, but there is a practical one: There are statements which I just believe involve too much formal build-up to be expressed understandable to a computer. And the proofs, too, get more lenghty and lenghty. And also, there probably will be many arguments needed for simple exercises which may be clear to you, but very cumbersome to implement.
Bottom line: I don’t think it’s worth it to avoid pen & paper. To many mathematicians, mathematics is a lot about images and ideas and arguments which are not formal in nature, and maybe even vague or fuzzy. Trying to force them to rigorosity can cost you a lot of time without a gain of insight, and maybe even leading you astray.
Edit: I misread your question: But the bottom line: Although it might be theoretically possible to do all the textbook problems in a programming language, I really don’t think it is advisable. And actually, I think you will find this out for yourself, if you try to do this. You probably will feel the immense slow-down, and you maybe even will need to pen-&-paper-do the exercise first to see how you could possibly implement them.
Not avoiding pen & paper doesn’t mean avoiding the computer, though.
implementthe proof of a theorem? Most problems in mathematics beyond introductory schooling are in terms of symbols and abstract relationships rather than particular numbers. It can certainly be helpful to see how these relationships behave in response to particular numbers in place of the symbols (and computers are good for evaluating that), but that can only take you so far. – Dan Bryant Apr 01 '14 at 18:39